Protective lining for canals and general earthwork



Nov. 2, 1943. E. .LBAIRD K 2,333,287

PROTECTIVE LINING FOR CANALS AND GENERAL ERTHWORK v Filed Nov. 20, 1939 "Mv s i@ l 3 nucntor:

hmmag ,Patented Nov. 2, 1943 PROTECTIVE LININ G FOR CANALS AND GENERAL EARTI-IWORK` Edgar J. Baird, Soda. Springs, yIdaho Application November 20, 1939, Serial N0. 305,223

(c1. rs1-) 4 Claims.

This invention relates to a protective lining for canals and general Water-confining or waterresisting earthwork. The principal objects of the invention are similar to those specified in my United States Patent Number 2,138,366, although the constitution of the present lining and the procedure followed in constructing it, are different from what is disclosed in the said patent.

The stated objects of the invention are to provide:

First. Means for preventing the loss of water through seepage.

Second. Means for killing or preventing vegetable growth.

Third. A lining substantially impervious to water and having great fiexibility, thereby serving to Aprevent cracking brought about by the tendency of a lining to buckle because of ,expansion and contraction or because of heaving or settling of the earth underneath.

Fourth. A lining which is easily and quickly installed but which is extremely durable and relatively inexpensive.

In the accompanying drawing,

Fig. 1 represents a plan of a fragmentary portion of a canal lined in accordance with the invention; and

Fig. 2, a fragmentary cross-section taken on the line 22 in Fig. 1, drawn to an enlarged scale.

According to the invention, the canal or other earthwork is excavated to the proper crosssection and graded to the proper alignment, but advantageously the natural condition of the earth below the boundary surfaces of the excavation is disturbed as little as possible. If the earth is not sufliciently compact by nature, it is made thoroughly so by any suitable means, well known or otherwise.

At a suitable stage of the proceeding, either before or after compacting the soil, a medium for destroying any vegetation that may be present, and to prevent as nearly as possible the starting of any future vegetation, is applied to thoroughly permeate the soil. Such a vegetationdestroying medium may advantageously be injected into the soil by means of well known devices. For this purpose there are preparations in everyday use, for instance, sodium chlorate compounded in various ways, or carbon bisulphide. y

The smoothed, Well-compacted banks and bottom of the excavation areV dressedwith an application of a water proofing liquid or semiliquid substance having pronounced penetrating properties with respect to the compacted earth. Such a liquid may advantageously consist of what is known commercially as SC-lA liquid asphalt, but I do not restrict myself to this particular substance. The specification for SC-lA liquid asphalt is as follows:

Water and sediment, percent 2.0 minus Flash point, deg. F 175 plus Saybolt furol viscosity at 122 F. sec 40-80 Total distillate'to 437 F. percent by volume g 3.0 minus Total distillate to 600 F. percent by f yvolume 25.0 minus Total distillate to 680 F. percent by Vvolume 30.0 minus Float of residue, 122 F. sec 50.0 minus Solubility of residue -in CS2 percent 99.0 plus Percent of residue sol. in CS2 in CCL 99.65 plus Percent asph. resi. of penetration- 50 plus The quantity of penetrating liquid required, and the exact Way of applying it, vary according to the nature and condition of a particular soil, and of the liquid itself. As a general rule, the quantity may be regarded as approximating a rate of from 0.50 to 0.75 of a gallon per square yard of surface exposed, depending upony the capacity of the ground to absorb the liquid. If necessary or desirable, the liquid may be thinned with an appropriate substance, or heated to increase its penetrating properties. Furthermore, whatever the physical condition of the liquid may be, it is frequently advantageous to apply it under pressure whereby still greater penetrating power and speed are obtained. Naturally, the depth to which the liquid penetrates the soil, varies with the conditions. The treatment just described, provides a flexible, waterproofed base upon which a waterproof mat is advantageously constructed in accordance with the following disclosure.

Upon the surface of the prepared base is spread a light coat of liquid bitumen, liquid asphalt, or other suitable substance, thus forming a tack coat for bonding the subsequent cona struction materials to the base, the tack coat being applied advantageously at the rate of approximately 0.25 of a gallon to a square yard .of surface. Frequently. it is necessary to apply the tack coat only to the banks of an excavation, since the movement of constructional equipment along the bottom surface of the excap vation insures good bondage along `that surface. A subsequent step, advantageously the next one, is to install a material for tying together or reinforcing all the component constructional substances in the form of the finished mat, which shall be continuous and substantially homogeneous throughout its superficial extent.

Such a reinforcing material may advantageously consist of a textile or reticular fabric composed of organic or inorganic substances, examples of cotton fabric supplied in strips of convenient f widths and of the proper grade and strength.

An advantageous method of procedure comprises laying the cotton fabric upon a bank of an excavation, immediately after and on top of, the application of the aforementioned tack coat, but leaving the further treatment of the bank until afterthe completion of the mat over the bottom surface of the excavation.

In constructing the bottom portion of the mat, the procedure may advantageously comprise laying a strip of cotton fabric longitudinally along and overlapping the adjacent bank strip sufficiently to insure continuity of reinforcing, the edge portions of this strip being securely fastened to the prepared base hereinbefore mentioned, for example, by means of heavy wire staples driven into the base. A lap of the strips of approximately l2 inchesV is usually satisfactory. vOver the strip of fabric thus laid, is spread a coat of heavy liquid bitumen or heavy liquid asphalt Well heated and advantageously applied by means of a suitable mechanical distributor having a sidebar nozzle and disposed to travel substantially parallel to the strip being operated upon. The quantity of coating liquid used in the operation just described, may be at the rate of about 0.35 to 0.50 of a gallon per square yard of surface.

Immediately following the coating operation, there is deposited upon its surface while still Wet, a layer of broken material that mayv advantageously be .mineral in character, such for example, as broken stone in the form of vsuitably sized chips. However, sand or gravel of the r proper kinds, or a mixture of them, may be found to be advantageous. 'I'he thickness of the layer should be suiicient to form a substantially homogeneous mass, usually not less than one inch in depth or thickness. As a next step, the layer is thoroughly impregnated with a suitable waterproofing binder applied at the rate of from 0.35 to 0.50 gallon per yard, which may consist of heavy liquid bitumen or heavy liquid asphalt. If desired, the waterproofing binder may be ymixed with the mineral material before it is deposited in the layer. On top of the material in the principal layer just described, is advantageously placed a course of relatively fine mineral material, such as, for example, sand or flnely crushed stone or crushed gravel, the purpose of which is tosettle down and fill any voids that may exist in the previously deposited layer, and also to act as a seal upon the bitumen or asphalt of that layer, thereby preventing any tendency thereof to bleed in its subsequent service. A somewhat different last spread of mineral for filling the voids in the layer of stone chips and as a preventative against bleeding, comprises an application of lne stone chips or both, the stone chips varying in size from squeegee 1A inch to 10 mesh or finer, distributed evenly at the rate of approximately 30 pounds per square yard, on top of the last coat of heavy bitumen or heavy asphalt.

In the event that stone chips are used for the principal layer course, these are advantageously supplied in sizes varying from 1A inch to inch, and are preferably produced by passing suitably crushed stone over` screens having square meshes. The chips are advantageously applied at the approximate rate of from to 60 pounds per.

square yard of surface, the distribution being eiected as evenly as possible, preferably by means of a suitable mechanical device.

In accomplishing the laying of the first bottom strip of fabric as hereinbefore described, a longitudinal margin of about six inches is left where the next strip of fabric is to be placed, in order to provide for lapping the next strip of fabric over the first. Assuming that the said next strip has been laid on the prepared base and stapled thereto as previously described, including the marginal portion overlapping, the subsequent procedural steps are followed as specified for the first strip of fabric up to and including the ilnal mineral coat as a protection against bleeding.

The laying of successive strips of fabric withl the water-proofing material overlaid, is continued substantially parallel to the first 'strip until the opposite bank of the excavation is reached, the last bank strip or strips being laid in a manner similar to the procedure hereinbefore stated relative to the first bank strips.

At the proper time or times and as the nal step in applying the improved protective lining, the mat, after the spreading of the sealing coat to prevent bleeding, is thoroughly compacted, for example, by passing a heavy roller over the mat as often as may be necessary to secure the desired results.

In finishing the side slopes of an excavation, it is frequently desirable to cut the quantity of squeegee stone chips or other fine mineral matter, down to approximately 20 pounds per square yard in the final spread, it being necessary however, to so completely cover the last coat of water-proofing liquid that bleeding shall be prevented as previously explained.

At points where a protective lining begins or ends, for example at the beginning or ending of a canal, and longitudinally along its banks, or along the banks of any excavation, it is advantageous to digl a trench into which a marginal portion of the textile or other fabric is extended and well imbedded in a mass of stone chips or other suitable material thoroughly impregnated with liquid bitumen or asphalt vand compacted to the proper degree. Such a construction is advantageous too, where a liningabuts against some other structure, such as a Wall or building foundation.

The principal utility of the trench construction just mentioned, is to strengthen the edge portions of the mat, and especially to prevent surface water from finding its Way to points directlyr underneath the mat. The filling material indicated at 20 in trench 2|, forms virtually a curtain wall.

In the drawing, the numeral I0 denotes the top 4chips or other Vmineral substance; and Il, a seal layer of mineral matter to ll voids in the stone chip layer and to prevent bleeding. The strips I4, forming a web course, may be fastened down by staples I8 along the simple edges, and by staples I9 along the edges of overlapping marginal portions.

Stated as a brief summary, the invention comprises a base of natural soil penetrated through infiltration or injection or otherwise, by a waterproong dressing which advantageously acquires a definite set In many cases, at a suitable stage `of the procedure, the base portion receives also a dressing of chemicals by means of which vegetable growth is at least largely exterminated or prevented or both. On this base is constructed a substantially water-resistant or Waterproof mat. An advantageous way of constructing the mat is to spread a primary deposit of cementitious bonding material followed by a superimposed web-reinforcement,v which, in turn, has spread upon it, a secondary deposit of cementitious material largely united to the bonding material through the interstices of the web course. On the secondary deposit is sprea-d a protective layer of suitable material, preferably mineral in character, the conditions of application being such that at leastthe bottom portion of the layer is united with the secondary cementitious deposit, while at least the major part -of the remaining portion is incorporated with cementitious material. The mat is preferably iinished 01T with a deposit of sealing material. The lining thus constructed, is flexible, both as regards the base and the mat, that is to say, the completed lining slumps like a quilt or blanket, Without cracking, in following ordinary changes in the configuration of the soil surface on which the lining rests.

Obviously, various minor changes can be made Without departing from the terms of the following claims.

Having fully described my invention, what I claim is:

1. A water-resisting lining for earthwork, including in combination, a base comprising compacted natural soil impregnated with a waterresisting medium which is substantially completely absorbed by the said natural soil, a tack coat of bonding material on the said base, a web of mat-reinforcing material on the bonding material, a deposit of cementitious material on the mat-reinforcing web, a deposit of relatively coarse mineral particles impregnated with a cementitious medium on the first-mentioned cementitious medium, and a deposit of sealing material on the c-ourse-particle layer to substantially prevent bleeding of the latter, all in the form of a matted unitary mass.

2. Lining an earthwork to make the same water-resisting, comprising, shaping the earth to the proper cross-section and to the proper alignment, compacting the earth, applying a vegetation destroying substance, applying an earth penetrating, Water-resistant dressing, depositing a bonding medium on the dressed earth, spreading a web of reinforcing material upon the bonding medium, spreading a deposit of cementitious material upon the said web and effecting a union between the cementitious material and the bonding medium, spreading a layer of mineral part'cles incorporate-d with a cementitious material upon the rst-mentioned cementitious material and effecting a union between the two, spreading a deposit of sealing material upon the cementitious deposit, and compacting the lining thus built up, into a unitary mass.

3. A water-resisting lining for earthwork, including in combination, a base of compacted natural soil impregnated to a considerable depth with a penetrating, Water-resisting medium which is substantially completely absorbed by the said natural soil; a tack coat of a flexible bonding material on the said base; a web of reinforcing material on the said bonding material; a tack coat of bonding material on the said web; a layer of relatively coarse mineral particles, mixed with a flexible, waterproof binder, on the last named bonding material; and a layer of relatively iine mineral particles on the said layer of coarse Imineral particles for substantially preventing bleeding of the said flexible, Waterproof binder; all in the form of a matted, unitary mass.

4. Lining an earthwork to make the same liquid resisting, comprising compacting the natural earth surface of the earthwork; applying to the said earth surface a penetrating, liquid-resisting medium of a type which is readily absorbed by the earth; allowing said earth to substantially completely absorb said liquid-resisting medium; applying a tack coat of a flexible bonding material to the compacted and impregnated earth surface; applying a web of reinforcing material to the said coat of bonding material; applying a tack coat of a flexible bonding material to said web; applying a layer of relatively coarse mineral particles, mixed with a flexible, liquid-resisting binder, to the last-named coat of bonding material; applying a layer of relatively fine mineral particles on the said layer of coarse mineral particles for substantially preventing bleeding of the said binder; and compacting the lining, as thus built up, into a unitary mass.

EDGAR J. BAIRD. 

